CoCoRaHS March Madness is a friendly competition to see which of the 50 states can recruit the most new volunteers to measure and report precipitation from their backyards, schools or work by March 31. The winning states get a traveling trophy, the CoCoRaHS Cup, to keep and exhibit until next year’s contest – like the NHL’s Stanley Cup. States compete in two categories to accommodate their differences in size and population.

Citizen science since 1998

Born in 1998 following major flooding in Fort Collins, CoCoRaHS is a citizen science network that has grown to more than 20,000 active participants. Volunteers are many and varied, ranging from individuals and families to schools, businesses and other institutions. All 50 states are represented, as well as Canada, Puerto Rico, the U.S. Virgin Islands, and soon, the Bahamas.

Volunteers measure precipitation that falls into their rain gauges, as well as recording
“zero” on days with no precipitation. They report their measurements on the CoCoRaHS website. The data are displayed and applied to situations ranging from water resources analysis to severe storm warnings.

“The more observers in a community, the better the knowledge of local water resources and impacts, including floods and droughts,” said Nolan Doesken, Colorado state climatologist. “CoCoRaHS is a great resource for anyone looking to see how much precipitation fell almost anywhere in the country.”

Data for hydrologists, emergency managers

And is this all just for fun? Far from it. Just a few examples of people or organizations who have used CoCoRaHS data: The National Weather Service, private meteorologists, hydrologists, emergency managers, news media, city utilities, insurance adjusters, the USDA, engineers, mosquito controllers, ranchers, farmers, outdoor and recreation interests, teachers, students, and neighbors in the community.